Ashington came from behind at the Bannister Prentice Stadium to record their first win in four games and stun Garforth in the process.
Garforth took a deserved first half lead when Dan Coupland arrowed a shot into the bottom corner.
The visitors turned the game on its head after the break and ran out deserved winners.
Garforth will need to regroup ahead of Saturdays home FA Trophy match.